Lawn-mower grinder.



I. MEYER.

LAWN MOWER GRINDER.

APPUCATION FILED 001.19. 1914.

Patented Sept. 28, 1915.

Fig. l. 23

WITNESSES:

A TTORN E Y COLUMBIA PLANOGRAPH co., \VASHINGTON, D, c.

ETQ.

ISBAEII. MEYER, 0F- SEAZIITLE, WASHINGTON.

Haw-MOWER eniivnnza,

ers, of which the following is; a specification.

This invention relates tolawnmower sharpeners; and-its object is. to produce a machine of this character whereby the cutting blades may be accurately and uniformly ground. I I

The invention consists in the novelconstruction and combination ofparts, as will be hereinafter described and claimed. r

In the accompanying drawings, Figure 1 is a plan view, shown partly in section, of an embodiment of the invention applied toa lawn-mower, only such partsthereof being shown as are necessary for-"an understanding of the invention. Fig. 2 is a vertical sectional' view through 2-2- of Fig.1. Fig. 3 is a detail front elevation of the indicating devices employed in adjusting; the grinding mechanism. Fig. 4 is a planview of the blade guide and Fig. 5 is a side elevation thereof.

The reference numeral 1 designates the side members or a mower frameand'2 is a transversely arranged bar. forming. part of said frame connecting the. side members 1-.

3 represents the helical cutterblades which are connected by the arms of spiders 1 to a shaft 5, as usual.

In carrying out my invention, there is provided bracket elements 6 which are detachably connected at their forward ends to the frame-bar 2 and have their rear ends supported by legs 7 which may be secured in adjusted positions by means: of set-screws 8. Extending through said brackets and rigidly secured to one of them, as by nuts 9, are parallel rods 10 and 11, whereof the former,10, serves as a track-rail fora oar-- riage C which supports the operatmgmech-' anism of the grinding appliances, and the other coacts with a hooked arm 12 of the carriage to prevent the forward tilting of the same. The rod 10 is, moreover, screwthreaded for engagement with an internally threaded hub or nut 13 formed on or provided in a worm-wheel 13 which is rigidly secured to said bushing and journaled in arms 11 provided on the carriage. The arms 14, by beinglocated at opposite sides of the wheel 13, prevent any independent axial Specification of Letters Patent.

Fri-tented Sept. 28., 1915*.

Applicatibrrfiled0ctober19, 1914. Serial N oi 867,288,

movement of the wheel with respect to the carriage and, in consequence, the turning of the wheel; and through the office of the screw rod 10, the carriage is caused to be moved in one lateral direction or the other. 15 represents a screwtor worm for operatmg said wheel and constitutes a shaft journaled in bearings on the carriage and pro- 7 vided with a cranL-handle 16. The carriage is provided with a forwardly directed arm comprising two members 17 and 18 hingedly connected by a pivotal pin 19 to allow a vertical swinging movement, to the forward one. parts which are connected by fastening bolts 20 extending through a slot 21in the one to permit its being moved in or out as may be required, according to the size of a mower.

In the outer part, 18 of such extensible member are provided bearing boxes for the transversely arranged arbor 2 2 of an emery wheel 23 and also a bearing for a longitudinally disposed shaft 24% whereby the emery wheel 23 is driven through the medium of bevel gears 25- and The shaft 2 1 extends intothe socket of a coupling 27 of a shaft 27 to allow relative endw-ise movements of the two shafts but no independent rotary movement, as for example, by forming the end'of' the shaft polygonal to fit into a correspondingly shaped socket in the coupling. Adjacent to the rear end ofshaft 27 is a bearing box 28 therefor which is swiveled as bytrunnions such as 28 Fig. 2, to a standard 29 provided'on the carriage.

30 is a gear wheel secured to shaft 27 and in mesh with a relatively large gear 31 secured to the worm-shaft 15 so as to transmita high speed rotary motion from the crank-handle 16 to the shafts 27 and 24': to

drive the emery wheel.

32 represents ajournal box for shaft 27 and is provided with trunnions, as 33 (Fig.

2)- whichare pivoted in blocks, as 34, rnovable vertically in slots provided in a guide- The latter, 18, in turn, is made of two Depending from a pin 43 provided near the periphery of the sector-gear is a rod 44 passing through a guide 45 and having at its lower end a foot 46. A spring 47 interposed between the guide 45 and the foot 46 of the rod serves to yieldingly press the latter against the shaft .27 and must move up or down with the same. I

The dial plate 38 is provided with graduated marks 48 which serve with the'finger 40 to indicate the relative elevations of the shaft. The emery wheel 23 is adjusted by regulating the effective lengths of the carriage arm elements 18 and 18 to a predetermined position with respect to the rods 10 and 11 and the axle 5 of the cutter-wheel to correspond to the bevels it is desired to grind tion to have the guide-face 50 (Fig. 4)

thereof contact with the inner face of a blade 3.

- For contacting against the outer face of the blade I provide two slotted bars 52 hav ing downwardly directed extremities 52 to bear against the blade. Inasmuch as the longitudinal curvature of blades vary with different makes of mowers and by reason that some are right and others left-hand helices, thebars 52 are rendered adjustable with respect to the branch 18 by means of thumb-screws 53 passing through the slots of the respective bars to engage in screwthreaded holes provided in such branch.

The machine is adjusted as to the position of the emery wheel with relation to a cutter blade-first, by regulating the arms- 18 and 18 of the carriage; and secondly, by

moving the carriage from one end of its travel to the other'and noting by the finger 40 and dial marks 48 the lowest elevation of the emery wheel, whereupon the screw 36 is adjusted to be encountered by the box 32 and prevent any lowering of the emery wheel below such elevation.

uniformly throughout its length. This is effected by the unbalanced weight of the carriage and attachments thereof bearing the emery wheel down upon the blade during the grinding ofthe same until arrested by the box 32 being stopped'by the screw 36.

The operation of the inventionis as follows; By turning the crank-handle 16'the shaft 15 is actuated to impart rotary motion to the wheel 13 and the latter, by the pro vision of the screw-threads in its hub, engaging threads of rod 10, effects the lateral travel of the carriage. The turning of the crank-handle also rotates the gear 31 where- Ihe purpose of limiting the downward movement of theemery wheel is to cause a blade to be ground by the shaft 27 is rotated through the medium of the gear 30. The shaft 24 which is coupled to the driven shaft 27 is rotated in unlson therewith and, through the gears 25 and 26, causes the emery wheel 23 to grind the cutter blade which is controlled by the guiding devices 50 and 52 as above explained. i Y r g What I claim as my invention, is'.

1. In a lawn-mower grinding machine, the

a shaft therefor, a swivel journal-box sup- 7 s0 'comblnatlon of a carrlage, an emery wheel,

ported by the carriage-and affording a bearing for an end of the shaft, means to regulate the elevation of the free end .of the shaft, and indicating devices influenced by said shaft for adjusting said regulating means. 1 w

2. In a lawn-mower grinding machine, a

carriage having an extensible arm hingedly connected thereto, an emery wheel, shafts for driving said wheel, and journaled in boxes respectively provided on the carriage and said arm, means to propel the carriage, and a driving means for operating both-the carriage-propelling means and the shaft.

Signed at Seattle, Washington, this 3rd 4 day of October, 1914. v

' V ISRAEL MEYER. V

Witnesses: V

PIERRE BARNES,

E. PETERSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D.' G. 

